Investigation of seasonal variations of nutrient in Satsuma mandarin trees

In this study, it was aimed to investigate the seasonal changes of nutrients in the Satsuma mandarins. Between April 2022 and March 2023, leaf samples were taken regularly every month from 30 Satsuma mandarin trees in the mandarin orchard in the Serik location of Antalya Batı Akdeniz Agricultural Research Institute, and N, P, K, Ca, Mg, Fe, Cu, Mn and Zn were analyzed in leaf samples. During the vegetation period, the nutrient concentrations of Satsuma mandarin leaves ranged between 1.88-2.65% for N, 0.14-0.28% for P, 0.89-1.82% for K, 1.84-4.64% for Ca, 0.17-0.27% for Mg, 74.15-143. 20 ppm for Fe, 11.57-18.97 ppm for Cu, 9.19-19-47 ppm for Mn and 7.88-19.63 ppm for Zn, and it was determined that the nutrient contents fluctuated during the vegetation period. The highest N, P, K, Ca, Mg, Fe and Mn concentrations were detected during fruit growth (June-July), the highest Cu concentration during flowering (April) and the highest Zn concentration during shoot formation (March). The lowest N, Ca, Mg and Mn concentrations occur during flowering (April-May), the lowest P, K and Fe concentrations were measured during shoot formation and winter dormancy (December-March), the lowest Cu concentrations were determined during fruit ripening (September-October) and the lowest during flowering (April-May). It was determined that the lowest Zn concentration was obtained during the harvest period (October-December). It has been determined that the most stable periods for all plant nutrients are generally September and October, which are the fruit ripening period. As a result, it was concluded that the data obtained play a critical role in determining the seasonal nutrient requirements of Satsuma mandarin and accordingly developing appropriate fertilization strategies. KEYWORDS: Antalya, Plant nutrients, Seasonal change, Satsuma mandarin